KR102300950B1 - Switch element, switch circuit, and warning circuit - Google Patents

Abstract

Without interlocking physical mechanical elements, while achieving miniaturization, the circuit is operated quickly. The insulating substrate 10, the 1st and 2nd electrodes 11 and 12 formed adjacently on the insulating substrate 10, and the 1st soluble conductor 13 mounted on the 1st electrode 11; It is formed in the insulated substrate 10, has the high melting-point metal body 15 with melting|fusing point higher than the 1st soluble conductor 13, The 1st soluble conductor by the heat|fever accompanying overcurrent electricity supply to the high melting-point metal body 15. (13) is melted, the 1st electrode 11 and the 2nd electrode 12 are connected through the molten conductor, and it is electrically short-circuited.

Description

SWITCH ELEMENT, SWITCH CIRCUIT, AND WARNING CIRCUIT

<Cross reference to related application>

This application claims the priority of Japanese Patent Application No. 2013-249565 (filed on December 2, 2013), The whole indication of the said application is taken in here for reference.

The present invention relates to a switch element and a switch circuit, and more particularly, to a switch element and a switch circuit that can be reduced in size and can be easily incorporated into an element operated by surface mounting.

As a switch element for operating an alarm, a fuse for an alarm is generally used. If an example of an alarm fuse is shown, as shown in FIG. 16 , in the fuse holder 100 , it is connected to the alarm circuit 105 for operating the alarm, respectively, and a pair of alarm contacts arranged apart from each other in normal use. (101, 102), a spring 103 for contacting the alarm contacts 101, 102, and a fuse wire 104 for holding the spring 103 at a position separated from the alarm contact 102 at a position spaced apart from the alarm contact 102. this is installed

The alarm contacts 101 and 102 actuate the alarm circuit 105 by contacting them, are formed of a conductive material having elasticity such as a leaf spring, and are disposed adjacent to each other. The alarm circuit 105 operates, for example, a buzzer or a lamp, and an alarm system by driving a thyristor or a relay circuit.

The spring 103 is held while being urged by the fuse wire 104 to a position spaced apart from the alarm contact 102 . Then, the spring 103 elastically returns when the fuse wire 104 is fused, and presses the alarm contact 102 to contact the alarm contact 101 .

The fuse wire 104 holds the spring 103 in an elastically displaced state, and when energized according to detection of various sensors, is fused by self-heating, thereby opening the spring 103 .

Japanese Patent Laid-Open No. 2001-76610

In the conventional fuse for an alarm, while holding the spring 103 in the elastically displaced state by the fuse wire 104, the fuse wire 104 is melted and the stress of the said spring 103 is released by the alarm contact point. (102) is physically pressed, and the structure which short-circuits between the alarm contacts (101, 102) by this is used. In such an alarm fuse, since the configuration in which the alarm circuit is activated by physical interlocking of mechanical elements is used, the alarm contact 101, 102 and the movable range of the spring 103 are secured. The structure becomes large and it becomes difficult to use it for the narrowed circuit, and manufacturing cost is also high.

In addition, since fusing the fuse wire 104 is essential for the short circuit of the alarm contacts 101 and 102, the alarm circuit is operated unless the fuse wire 104 is blown by continuously passing a current exceeding the rating. can't do it

Accordingly, an object of the present invention is to provide a switch element and a switch circuit that operate a circuit quickly while achieving miniaturization without interlocking physical mechanical elements, and an alarm circuit using the same.

In order to solve the above-mentioned problem, the switch element which concerns on this invention is an insulating substrate, and the 1st soluble conductor mounted on the said insulating substrate, the 1st, 2nd electrode formed adjacently, and the said 1st electrode, and , is formed on the insulating substrate, has a high melting point metal body having a higher melting point than the first soluble conductor, melts the first soluble conductor by heat generated by energization of the high melting point metal body, and the first soluble conductor The first electrode and the second electrode are connected through the molten conductor of the conductor to electrically short circuit.

Moreover, the switch circuit which concerns on this invention is mutually open and connected with an external circuit, has the 1st and 2nd electrodes in which the soluble conductor was mounted in at least one side, The said external circuit by the said 1st and 2nd electrode being short-circuited. and a fuse having a melting point higher than the melting point of the soluble conductor and connected to a functional circuit formed electrically independent of the switch unit, and generating heat accompanying energization of the fuse by the functional circuit. By this, the said soluble conductor is melted, the said 1st, 2nd electrode is short-circuited with the molten conductor of the said soluble conductor, and the said external circuit is operated.

In addition, the alarm circuit according to the present invention is open to each other, has a soluble conductor mounted on at least one of the first and second electrodes, and the first and second electrodes are short-circuited by a switch unit to operate the alarm a control circuit comprising: a circuit; a fuse formed electrically independent of the operation circuit and having a melting point higher than that of the soluble conductor; and a functional circuit in which the fuse is connected in series to a power source; The soluble conductor is melted by the heat generated at the time of melting of the fuse along with the overcurrent flowing at the time of abnormality, and the first and second electrodes are short-circuited by the molten conductor of the soluble conductor, thereby operating the alarm.

According to the present invention, since it can be configured without using mechanical elements such as springs or alarm contacts and without physically interlocking the mechanical elements, it can be designed compactly within the plane of the insulating substrate, and Mounting is also possible in the mounting area. Further, according to the present invention, since the switch is turned on by the heat of the high-melting-point metal body, it is possible to detect an abnormal overcurrent and operate the circuit without the need to cut off the fuse. Further, according to the present invention, the insulating substrate can be surface mounted by reflow mounting or the like, so that it can be mounted easily even in a narrowed mounting area.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the state before operation of the switch element to which this invention was applied, (A) is a top view, (B) is AA' sectional drawing, (C) is a circuit diagram.
It is a figure which shows the state before the operation|movement of the switch element which mounted the 2nd soluble conductor on the 2nd electrode, (A) is a top view, (B) is AA' sectional drawing, (C) is a circuit diagram.
3 is a view showing a state in which the high-melting-point metal body of the switch element generates heat, and the first and second electrodes are short-circuited through the molten conductor of the soluble conductor, (A) is a plan view, (B) is AA' cross-sectional view, (C) is a circuit diagram.
Fig. 4 is a view showing a state in which a high-melting-point metal body of a switch element is melted, (A) is a plan view, (B) is a cross-sectional view AA', (C) is a circuit diagram.
Fig. 5 is a circuit diagram showing an alarm circuit.
It is a figure which shows the switch element which connected the high-melting-point metal body and the 1st electrode, (A) is a top view, (B) is AA' sectional drawing, (C) is a circuit diagram.
7 is a cross-sectional view showing a switch element in which a cover electrode is formed on a cover member.
It is a figure which shows the switch element which superposed the high-melting-point metal body, 1st, 2nd electrode, and 1st, 2nd soluble conductor on the surface of an insulating substrate, (A) is a top view, (B) is AA' cross-section.
9 is a diagram showing a switch element in which a high-melting-point metal body is formed on the back surface of an insulating substrate and overlapped with first and second electrodes and first and second soluble conductors formed on the surface of the insulating substrate, (A ) is a plan view, (B) is a cross-sectional view AA'.
10 is a perspective view showing a soluble conductor having a high-melting-point metal layer and a low-melting-point metal layer and having a covering structure, (A) is a high-melting-point metal layer as an inner layer and a low-melting-point metal layer covering the structure with a low-melting-point metal layer, (B) ) shows a structure in which a low-melting-point metal layer is used as an inner layer and is coated with a high-melting-point metal layer.
11 is a perspective view showing a soluble conductor having a laminated structure of a high-melting-point metal layer and a low-melting-point metal layer, (A) showing a two-layer structure, (B) showing a three-layer structure of an inner layer and an outer layer.
It is sectional drawing which shows the soluble conductor provided with the multilayer structure of a high-melting-point metal layer and a low-melting-point metal layer.
13 is a plan view showing a soluble conductor in which a linear opening is formed on the surface of a high-melting-point metal layer and the low-melting-point metal layer is exposed, (A) is an opening formed along the longitudinal direction, (B) is a width direction Accordingly, an opening is formed.
14 is a plan view showing a soluble conductor in which a circular opening is formed on the surface of the high-melting-point metal layer and the low-melting-point metal layer is exposed.
15 is a plan view showing a soluble conductor in which a circular opening is formed in a high-melting-point metal layer, and a low-melting-point metal is filled therein.
Fig. 16 is a view showing a conventional alarm element, (A) is a cross-sectional view before operation, (B) is a cross-sectional view after operation.

Hereinafter, a switch element, a switch circuit, and an alarm circuit to which the present invention is applied will be described in detail with reference to the drawings. In addition, this invention is not limited only to the following embodiment, It goes without saying that various changes are possible within the range which does not deviate from the summary of this invention. In addition, drawings are schematic, and the ratio of each dimension, etc. may differ from an actual thing. Specific dimensions and the like will have to be determined in consideration of the following description. In addition, it goes without saying that the drawings also contain portions in which the relationship and ratio of the dimensions are different from each other.

[Switch element]

As shown in FIG. 1, the switch element 1 to which the present invention is applied includes an insulating substrate 10, and first and second electrodes 11 and 12 formed adjacent to each other on the insulating substrate 10, and a second It is formed in the 1st soluble conductor 13 mounted on the 1 electrode 11, and the insulating substrate 10, and has the high-melting-point metal body 15 whose melting|fusing point is higher than the 1st soluble conductor 13. Fig. 1A is a plan view of the switch element 1 except for the cover member 20, Fig. 1B is a sectional view taken along line A-A', and Fig. 1C is a circuit diagram.

In the switch element 1, the first and second electrodes 11 and 12 are connected to an alarm 31 including a buzzer, a lamp, or an alarm system, and the first 1 By melting the soluble conductor 13, between the 1st, 2nd electrodes 11 and 12 is short-circuited by this molten conductor, and the buzzer, the lamp|ramp, the alarm system etc. which are the alarm devices 31 are operated.

The insulating substrate 10 is formed in a substantially rectangular shape using, for example, an insulating member such as alumina, glass ceramics, mullite, or zirconia. In addition, although the material used for printed wiring boards, such as a glass epoxy board|substrate and a phenol board|substrate, may be used for the insulating board|substrate 10, it is necessary to pay attention to the temperature at the time of melting of the 1st soluble conductor 13.

[First, Second Electrodes]

The first and second electrodes 11 and 12 are opened on the surface 10a of the insulating substrate 10 by being disposed close to each other and spaced apart from each other. Moreover, the 1st soluble conductor 13 mentioned later is mounted on the 1st electrode 11. As shown in FIG. As for the 1st, 2nd electrodes 11 and 12, the fusion|melting conductor of the 1st soluble conductor 13 is 1st, 2nd electrodes 11 and 12 when the high-melting-point metal body 15 heat|fever-generates with electricity supply. Agglomerate, bond across the liver, and constitute a switch 2 that is short-circuited through this molten conductor.

In addition, the switch element 1 may mount the 2nd soluble conductor 14 on the 2nd electrode 12, as shown in FIG. As for the switch element 1, by providing the 1st, 2nd soluble conductors 13 and 14, more molten conductors aggregate over between the 1st, 2nd electrodes 11 and 12, and it is quicker and more reliably, The first and second electrodes 11 and 12 may be short-circuited. Below, the switch element 1 which formed the 1st soluble conductor 13 on the 1st electrode 11 shown in FIG. 2, and formed the 2nd soluble conductor 14 on the 2nd electrode 12. ) will be described as an example.

The 1st, 2nd electrodes 11 and 12 can make it easy to aggregate the fusion|melting conductor of the 1st, 2nd soluble conductors 13 and 14 by heating with the high-melting-point metal body 15.

The first and second electrodes 11 and 12 have external connection terminals 11a and 12a formed on side edges 10b and 10c of the insulating substrate 10, respectively. The first and second electrodes 11 and 12 are connected to the alarm 31 via these external connection terminals 11a and 12a, and when the switch element 1 operates, it is a power supply path to the alarm 31. do.

The 1st, 2nd electrodes 11 and 12 can be formed using general electrode materials, such as Cu and Ag. Further, on the surfaces of the first and second electrodes 11 and 12, a film such as Ni/Au plating, Ni/Pd plating, and Ni/Pd/Au plating is coated by a known method such as plating treatment. desirable. Thereby, the switch element 1 can prevent oxidation of the 1st, 2nd electrodes 11 and 12, and can hold|maintain the fusion conductor of the 1st, 2nd soluble conductors 13 and 14 reliably. Moreover, when reflow-mounting the switch element 1, the solder 17 for connection which connects the 1st, 2nd soluble conductors 13 and 14, or the 1st, 2nd soluble conductors 13 and 14 By melting the low-melting-point metal forming the outer layer, it is possible to prevent corrosion (solder corrosion) of the first and second electrodes 11 and 12 .

[High melting point metal body]

The high-melting-point metal body 15 is a conductive member that generates heat when energized, and includes, for example, W, Mo, Ru, Cu, Ag, or an alloy having these as a main component. The high-melting-point metal body 15 can be formed by mixing these alloys, compositions, or powders of the compound with a resin binder or the like to form a paste using a screen printing technique, then pattern-forming and firing.

The high-melting-point metal body 15 is arranged side by side with the first and second electrodes 11 and 12 on the surface 10a of the insulating substrate 10 . Thereby, when the high-melting-point metal body 15 generates heat accompanying electricity, it can melt the 1st, 2nd soluble conductors 13 and 14 mounted on the 1st, 2nd electrodes 11 and 12. .

In the high-melting-point metal body 15 , external connection terminals 15a are formed on the side edges 10b and 10c of the insulating substrate 10 . The high-melting-point metal body 15 is connected to the function circuit 32 serving as an operation trigger of the alarm 31 via the external connection terminal 15a, and generates heat due to overcurrent accompanying abnormality of the function circuit 32. .

In addition, the high-melting-point metal body 15 is a position adjacent to the first and second soluble conductors 11 and 12, and is relatively thin, and the heating part 15b that locally generates heat at a high temperature by concentrating the current. is formed By forming the heat generating part 15b in the position adjacent to the 1st, 2nd soluble conductors 11 and 12, the high-melting-point metal body 15 melts the 1st, 2nd soluble conductors 13 and 14 efficiently Thus, the first and second electrodes 11 and 12 can be short-circuited quickly.

As shown in Fig. 2, in the high-melting-point metal body 15, when the functional circuit 32 is operating normally, an appropriate current within the rating flows. And, the high-melting-point metal body 15 generates heat when an overcurrent flows due to abnormality in the functional circuit 32, and as shown in FIG. 3 , the first and second soluble conductors 13 and 14 are melted, and the fusion The first and second electrodes 11 and 12 are short-circuited through the conductor. Even after that, the high-melting-point metal body 15 continues to generate heat, and as shown in Fig. 4, is fused by its own Joule heat. Thereby, in the high-melting-point metal body 15, the overcurrent caused by the abnormality of the functional circuit 32 is interrupted|blocked, and heat_generation|fever is stopped. That is, while melting the 1st, 2nd soluble conductors 13 and 14, the high-melting-point metal body 15 functions as a fuse which interrupts|blocks its own power supply path by self-heating.

In addition, the high-melting-point metal body 15 is melted in the heat-generating portion 15b by forming the heat-generating portion 15b that becomes a high temperature locally. At this time, since the high-melting-point metal body 15 has a relatively thin heat generating portion 15b, the arc discharge generated at the time of melting is also small-scale, and together with the coating effect of the insulating layer 16 to be described later, The scattering of the molten conductor can be prevented.

In addition to pattern formation by printing the above-described conductive paste, the high-melting-point metal body 15 may be formed using a high-melting-point metal foil such as copper foil or silver foil, or a high-melting-point metal wire such as a copper wire or a silver wire. In addition, when the high-melting-point metal body 15 is formed using a high-melting-point metal foil or a high-melting-point metal wire, the problem of leakage of the molten conductor after melting of the high-melting-point metal body 15 is smaller than that of the conductive pattern. , a ceramic substrate having excellent thermal conductivity and capable of rapidly melting the first and second soluble conductors 13 and 14 as the insulating substrate 10 can be appropriately used.

[insulation layer]

The first and second electrodes 11 and 12 and the high-melting-point metal body 15 are covered with an insulating layer 16 on the surface 10a of the insulating substrate 10 . The insulating layer 16 protects and insulates the first and second electrodes 11 and 12 and the high-melting-point metal body 15 and prevents arc discharge at the time of melting of the high-melting-point metal body 15 . It is formed to contain, for example, a glass layer.

1 and 2 , the insulating layer 16 covers the heat generating portion 15b of the high-melting-point metal body 15 and the tip portions 11b of the first and second electrodes 11 and 12 . , 12b) is formed on the region except for. That is, as for the 1st, 2nd electrodes 11 and 12, the front-end|tip parts 11b, 12b are exposed from the insulating layer 16, The 1st, 2nd soluble conductors 13 and 14 mentioned later can aggregate and couple|bond together. is to be done

Further, in the first and second electrodes 11 and 12 , an opening 16a is formed in a part of the insulating layer 16 . The first and second electrodes 11 and 12 are provided with a solder 17 for connection at the tip portions 11b and 12b and the opening 16a, and the tip portion 11b, The 1st, 2nd soluble conductors 13 and 14 are supported on the insulating layer 16 between 12b) and the opening part 16a.

Further, an insulating layer 16 made of glass or the like may be formed between the high-melting-point metal body 15 and the insulating substrate 10 . Thereby, the insulation resistance after interruption|blocking of the high-melting-point metal body 15 can be made high.

[1st, 2nd soluble conductor]

The 1st, 2nd soluble conductors 13 and 14 mounted on the 1st, 2nd electrodes 11 and 12 through the insulating layer 16 are melt|dissolving rapidly by heat_generation|fever of the high-melting-point metal body 15. Any metal can be used, and for example, a low-melting-point metal such as solder or Pb-free solder containing Sn as a main component can be suitably used.

In addition, the 1st, 2nd soluble conductors 13 and 14 may contain a low-melting-point metal and a high-melting-point metal. As the low melting point metal, it is preferable to use solder or Pb-free solder containing Sn as a main component, and as the high melting point metal, it is preferable to use Ag, Cu, or an alloy containing these as a main component, or the like. By containing a high-melting-point metal and a low-melting-point metal, when reflow-mounting the switch element 1, even if a reflow temperature exceeds the melting temperature of a low-melting-point metal and a low-melting-point metal melts, the outside of a low-melting-point metal The outflow to a furnace can be suppressed and the shape of the 1st, 2nd soluble conductors 13 and 14 can be maintained. In addition, by melting the low-melting-point metal in a melting trial, melting the high-melting-point metal (solder corrosion) enables rapid fusion cutting at a temperature below the melting point of the high-melting-point metal. In addition, the 1st, 2nd soluble conductors 13 and 14 can be formed with various structures so that it may demonstrate later.

Moreover, as for the 1st, 2nd soluble conductors 13 and 14, it is preferable that the flux 18 is apply|coated for oxidation prevention, wettability improvement, etc.

[Switch circuit/Alarm circuit]

The switch element 1 as described above has a circuit configuration as shown in Fig. 2C. That is, the switch element 1 is opened when the first electrode 11 and the second electrode 12 are normal (FIG. 2(C)), and the first, When the 2nd soluble conductors 13 and 14 melt|dissolve, the switch 2 short-circuited through the said molten conductor will be comprised (FIG.3(B)). In addition, each of the external connection terminals 11a and 12a of the first and second electrodes 11 and 12 constitutes both terminals of the switch 2 .

And the switch element 1 is built-in and used in the alarm circuit 30, for example. 5 : is a figure which shows an example of the circuit structure of the alarm circuit 30. As shown in FIG. The alarm circuit 30 is formed electrically independent of the operation circuit 33 for operating the alarm 31 by the switch 2 of the switch element 1, and the operation circuit, the first and second soluble conductors ( A fuse including a high-melting-point metal body 15 having a higher melting point than those of 13 and 14 is provided with a control circuit 34 having a functional circuit connected in series to a power supply.

As shown in Fig. 5, in the switch element 1, both external connection terminals 11a and 12a of the switch 2 are connected to an alarm device 31 including a buzzer, a lamp, an alarm system, or the like. In the switch element 1 , both external connection terminals 15a of the high-melting-point metal body 15 are connected to the functional circuit 32 .

The switch element 1 having such a configuration has a high melting point metal body 15 formed adjacent to the first and second electrodes 11 and 12 constituting the switch 2 for operating the alarm 31 . ) melts the 1st, 2nd soluble conductors 13 and 14 by heat_generation|fever, and short-circuits through this molten conductor. That is, the switch element 1 is configured to be physically and electrically independent of the high-melting-point metal body 15 and the first and second electrodes 11 and 12 , and is formed by the heat of the high-melting-point metal body 15 . , it short-circuits when the 2nd soluble conductors 13 and 14 melt|dissolve, that is, take the structure which interlock|cooperates by connecting thermally.

Therefore, since the switch element 1 can be configured without using mechanical elements such as springs or alarm contacts and without physically interlocking the mechanical elements, it is compactly designed within the plane of the insulating substrate 10 . This makes it possible to mount even in a narrowed mounting area. Moreover, the switch element 1 can aim at reduction of the number of parts and the number of manufacturing processes, and can achieve cost reduction. In addition, the switch element 1 can be surface mounted on the insulating substrate 10 by reflow mounting or the like, and can be easily mounted even in a narrowed mounting area.

In actual use, an overcurrent flows through the high-melting-point metal body 15 due to a problem in the functional circuit 32 of the switch element 1 . Then, as shown in FIG.3(A), the high-melting-point metal body 15 heat|fever-generates, Thereby, the 1st, 2nd soluble conductors 13 and 14 melt|fuse. The molten conductors of the 1st, 2nd soluble conductors 13 and 14 have a wider area compared with the opening part 16a, and the 1st, 2nd electrodes 11 and 12 heated by the high-melting-point metal body 15 further. It aggregates on each tip part 11b, 12b of the and couple|bonds. Thereby, the switch element 1 can short-circuit between the 1st, 2nd electrodes 11 and 12, and the alarm 31 can be operated. That is, in the switch element 1, the switch 2 is turned on (FIG. 3(C)). In the alarm circuit 30 , when the switch 2 of the switch element 1 is turned on, the alarm 31 is operated by the operation circuit 33 .

At this time, the switch element 1 forms the heat generating part 15b thinly formed in the vicinity of the 1st, 2nd soluble conductors 13 and 14 of the high-melting-point metal body 15, The high resistance heat generating part 15b ) becomes high temperature, it can melt|melt the 1st, 2nd soluble conductors 13 and 14 efficiently, and can short-circuit the 1st, 2nd electrodes 11 and 12 quickly. In addition, in the high-melting-point metal body 15, only the high-resistance heat generating portion 15b becomes locally high, and both external connection terminals 15a facing the side edges are maintained at a relatively low temperature with a heat dissipation effect. Therefore, in the switch element 1, the solder for mounting the external connection terminal 15a does not melt.

As shown in FIG. 4 , even after the short circuit between the first and second electrodes 11 and 12 , the refractory metal body 15 continues to generate heat and is blocked by its own Joule heat (FIG. 4(A) ) , (B)). Thereby, electricity supply by the function circuit 32 is interrupted|blocked in the switch element 1, and heat_generation|fever is stopped (FIG.4(C)). At this time, in the switch element 1, since the high-melting-point metal body 15 is coat|covered with the insulating layer 16, arc discharge can be suppressed and explosive scattering of a molten conductor can be suppressed. Moreover, by forming the thin heating part 15b formed in the high-melting-point metal body 15, a melting|fusing point can be narrowed and the quantity of the scattered molten conductor can be reduced.

Thus, in the switch element 1, the 1st, 2nd soluble conductors 13 and 14 reliably, when the high-melting-point metal body 15 with higher melting|fusing point heats than the 1st, 2nd soluble conductors 13 and 14, heat_generation|fever It is melted before the temporary high-melting-point metal body 15, and the first and second electrodes 11 and 12 can be short-circuited. That is, in the switch element 1, the interruption|blocking of the high-melting-point metal body 15 is not made into the requirement which short-circuits the 1st, 2nd electrodes 11 and 12. Therefore, the switch element 1 can be used as an alarm switch which conveys that the electric current exceeding the rating of the high-melting-point metal body 15 flowed with the abnormality of the functional circuit 32. As shown in FIG.

In addition, the high-melting-point metal body 15 is cut off by its own Joule heat, thereby automatically stopping heat generation. Therefore, the switch element 1 does not need to provide a mechanism for regulating the power supply by the functional circuit 32, so that heat generation of the high-melting-point metal body 15 can be stopped with a simple configuration, and the overall element size can be reduced. can be promoted

[Connection of high melting point metal body and first electrode]

Moreover, the switch element 1 connects the high melting-point metal body 15 and the 1st electrode 11 in which the 1st soluble conductor 13 is mounted, the connection part 19 as shown in FIG. may be formed. The connection part 19 is patterned in the same process as the high-melting-point metal body 15 and the 1st electrode 11 using the same conductive material as the high-melting-point metal body 15 and the 1st electrode 11, for example. It can be formed by forming.

By connecting the high-melting-point metal body 15 and the first electrode 11, the switch element 1 connects the connecting portion 19 and the first electrode 11 when the high-melting-point metal body 15 generates heat by energization. Through the heat is transferred to the first soluble conductor 13, it can be melted faster. Accordingly, the connecting portion 19 is preferably formed of a metal material such as Ag or Cu having excellent thermal conductivity.

[Cover member/cover part electrode]

In the switch element 1 , a cover member 20 for protecting the inside is attached on an insulating substrate 10 . The inside of the switch element 1 is protected by the insulating substrate 10 being covered with the cover member 20. As shown in FIG. The cover member 20 has a side wall 21 constituting a side surface of the switch element 1 and a ceiling surface portion 22 constituting an upper surface of the switch element 1 , and the side wall 21 is an insulating substrate 10 . By being connected to the phase, it becomes a cover which blocks the inside of the switch element 1 . This cover member 20 is formed using, for example, a member having insulation properties, such as a thermoplastic plastic, ceramics, or glass epoxy substrate, similarly to the above-mentioned insulating substrate 10 .

In addition, as shown in FIG. 7 , in the cover member 20 , the cover electrode 23 may be formed on the inner surface side of the ceiling surface portion 22 . The cover electrode 23 is formed at an overlapping position between the respective tip portions 11b and 12b of the first and second electrodes 11 and 12 . When the high-melting-point metal body 15 generates heat and the first and second soluble conductors 13 and 14 are melted, the cover electrode 23 is agglomerated on the first and second electrodes 11 and 12. When a molten conductor contacts and spreads widely, the allowable amount for holding a molten conductor can be increased, and the 1st, 2nd electrodes 11 and 12 can be short-circuited more reliably.

[Arrangement of high melting point metal body: Modification 1]

In addition, on the surface of an insulating substrate, the switch element to which this invention was applied WHEREIN: You may make a high-melting-point metal body and a 1st, 2nd electrode overlap. In addition, in the following description, about the structure similar to the switch element 1 mentioned above, the same code|symbol is attached|subjected and the detail is abbreviate|omitted. In this switch element 40, as shown in FIG. 8, the high-melting-point metal body 15 is formed over the mutually opposing side edges 10d, 10e of the surface 10a of the insulated substrate 10. As shown in FIG. Moreover, in the switch element 40, the 1st, 2nd electrodes 11 and 12 are formed in the mutually opposing side edges 10b, 10c of the surface 10a of the insulating substrate 10. As shown in FIG.

The high-melting-point metal body 15 is covered with the first insulating layer 41 in the substantially central portion of the insulating substrate 10 . In the high-melting-point metal body 15 , external connection terminals 15a are respectively formed on the side edges 10d and 10e of the insulating substrate 10 . Further, in the high-melting-point metal body 15, a middle portion where the first and second electrodes 11 and 12 overlap is formed thinner than both ends, so that a heat generating portion 15b that generates heat at a high temperature is formed.

The first and second electrodes 11 and 12 have external connection terminals 11a and 12a formed on the side edges 10b and 10c of the insulating substrate 10, respectively. Further, the first and second electrodes 11 and 12 are formed over the upper surface of the first insulating layer 41 from the side edges 10b and 10c, and distal ends of each other on the upper surface of the first insulating layer 41 . (11b, 12b) is opened by being spaced apart as it approaches. Further, the first and second electrodes 11 and 12 are covered with the second insulating layer 42 except for the tip portions 11b and 12b.

An opening 42a is formed in a part of the second insulating layer 42 . Then, as for the first and second electrodes 11 and 12, solder for connection is formed at the tip portions 11b, 12b and the opening 42a, and the tip portions 11b, 12b and the opening 42a are formed by the connection solder. ), the 1st, 2nd soluble conductors 13 and 14 are supported on the 2nd insulating layer 42. Thereby, at least one part of the front-end|tip parts 11b and 12b of the 1st, 2nd electrodes 11 and 12, and the 1st, 2nd soluble conductors 13 and 14 is the heat generating part ( of the high-melting-point metal body 15) 15b) is superimposed. Moreover, on the 1st, 2nd soluble conductors 13 and 14, the flux 18 is apply|coated for oxidation prevention, the improvement of wettability, etc.

As for the 1st, 2nd insulating layers 41 and 42, similarly to the insulating layer 16 of the switch element 1 mentioned above, insulating materials, such as glass, can be used suitably.

According to such a switch element 40, it overlaps with the heat generating part 15b of the high-melting-point metal body 15, and the 1st, 2nd electrodes 11 and 12, and the 1st, 2nd soluble conductors 13 and 14 is disposed, the first and second soluble conductors 13 and 14 can be rapidly melted by the heat generated by the heat generating portion 15b, and the first and second electrodes 11 and 12 can be short-circuited. At this time, the switch element 40 includes the first and second insulating layers 41 and 42 made of glass, etc. interposed therebetween, the heating part 15b and the first and second electrodes 11 and 12 and the first, Since the 2nd soluble conductors 13 and 14 are laminated|stacked continuously, the heat|fever of the heat generating part 15b can be conducted efficiently.

[Arrangement of high melting point metal body: Modification 2]

In the switch element to which the present invention is applied, the first and second electrodes are formed on the surface of the insulating substrate, and the high-melting-point metal body is formed on the back surface of the insulating substrate, whereby the high-melting-point metal body and the first and second electrodes are formed. They may be nested. In addition, in the following description, about the structure similar to the switch element 1 mentioned above, the same code|symbol is attached|subjected and the detail is abbreviate|omitted. In this switch element 50, as shown in FIG. 9, the high-melting-point metal body 15 is formed over the mutually opposing side edges 10d, 10e of the back surface 10f of the insulated substrate 10. As shown in FIG. Moreover, in the switch element 50, the 1st, 2nd electrodes 11 and 12 are formed in the mutually opposing side edges 10b, 10c of the surface 10a of the insulating substrate 10. As shown in FIG.

The high-melting-point metal body 15 is covered with the first insulating layer 51 in the substantially central portion of the insulating substrate 10 . In the high-melting-point metal body 15 , external connection terminals 15a are respectively formed on the side edges 10d and 10e of the insulating substrate 10 . Further, in the high-melting-point metal body 15, a middle portion where the first and second electrodes 11 and 12 overlap is formed thinner than both ends, so that a heat generating portion 15b that generates heat at a high temperature is formed.

The first and second electrodes 11 and 12 have external connection terminals 11a and 12a formed on the side edges 10b and 10c of the insulating substrate 10, respectively. In addition, the first and second electrodes 11 and 12 are spaced apart from the side edges 10b and 10c while the respective front ends 11b and 12b approach each other in the substantially central portion of the surface 10a of the insulating substrate 10 . As such, it is open. Further, the first and second electrodes 11 and 12 are covered with the second insulating layer 52 except for the tip portions 11b and 12b.

An opening 52a is formed in a part of the second insulating layer 52 . Then, as for the first and second electrodes 11 and 12, solder for connection is formed in the tip portions 11b, 12b and the opening 52a, and the tip portions 11b, 12b and the opening 52a are formed by the solder for connection. ), the 1st, 2nd soluble conductors 13 and 14 are supported on the 2nd insulating layer 52. Thereby, at least one part of the front-end|tip parts 11b and 12b of the 1st, 2nd electrodes 11 and 12, and the 1st, 2nd soluble conductors 13 and 14 is the heat generating part ( of the high-melting-point metal body 15) 15b) is superimposed. Moreover, on the 1st, 2nd soluble conductors 13 and 14, the flux 18 is apply|coated for oxidation prevention, wettability improvement, etc.

As for the 1st, 2nd insulating layers 51 and 52, similarly to the insulating layer 16 of the switch element 1 mentioned above, insulating materials, such as glass, can be used suitably.

According to such a switch element 50, it overlaps with the heat generating part 15b of the high-melting-point metal body 15, and the 1st, 2nd electrodes 11 and 12 and the 1st, 2nd soluble conductors 13 and 14 is disposed, the first and second soluble conductors 13 and 14 can be rapidly melted by the heat generated by the heat generating portion 15b, and the first and second electrodes 11 and 12 can be short-circuited. At this time, the switch element 50 is the insulating substrate 10, by using a ceramic substrate or the like excellent in thermal conductivity, the high-melting-point metal body 15, the first and second soluble conductors 13, 14 are formed on the surface Since it can heat equivalently to the case where it forms on the same surface as , it is preferable.

[Modified example of soluble conductor]

As mentioned above, any one or all of the 1st, 2nd soluble conductors 13 and 14 may contain a low-melting-point metal and a high-melting-point metal. The high-melting-point metal layer 60 contains Ag, Cu, or an alloy containing these as a main component, and the low-melting-point metal layer 61 contains Pb-free solder containing Sn as a main component, or the like. At this time, the first and second soluble conductors 13 and 14 are, as shown in FIG. You may use a soluble conductor. In this case, the 1st, 2nd soluble conductors 13 and 14 are good also as a structure in which the whole surface of the high-melting-point metal layer 60 was coat|covered with the low-melting-point metal layer 61, A pair of mutually opposing side surfaces Except, it may be a coated structure. The coating structure by the high-melting-point metal layer 60 or the low-melting-point metal layer 61 can be formed using well-known film-forming techniques, such as plating.

In addition, as shown in FIG. 10(B), as for the 1st, 2nd soluble conductors 13 and 14, the low-melting-point metal layer 61 is formed as an inner layer, and the high-melting-point metal layer 60 is formed as an outer layer. You may use a soluble conductor. Also in this case, the 1st, 2nd soluble conductors 13 and 14 are good also as a structure in which the whole surface of the low-melting-point metal layer 61 was coat|covered with the high-melting-point metal layer 60, A pair of mutually opposing side surfaces It may have a coated structure except for

Moreover, as shown in FIG. 11, the 1st, 2nd soluble conductors 13 and 14 are good also as a laminated structure in which the high-melting-point metal layer 60 and the low-melting-point metal layer 61 were laminated|stacked.

In this case, the 1st, 2nd soluble conductors 13 and 14 are laminated|stacked on the lower layer supported by the 1st, 2nd electrodes 11 and 12, and the lower layer, as shown to Fig.11 (A). It is formed as a two-layer structure including an upper layer, and a low-melting-point metal layer 61 serving as an upper layer may be laminated on the upper surface of the high-melting-point metal layer 60 serving as a lower layer, and vice versa. You may laminate|stack the high-melting-point metal layer 60 used as an upper layer on the upper surface. Alternatively, the first and second soluble conductors 13 and 14 may be formed as a three-layer structure including an inner layer and an outer layer laminated on the upper and lower surfaces of the inner layer, as shown in FIG. The low-melting-point metal layer 61 serving as the outer layer may be laminated on the upper and lower surfaces of the high-melting-point metal layer 60 of do.

In addition, as shown in FIG. 12, the 1st, 2nd soluble conductors 13 and 14 are good also as a multilayer structure of 4 or more layers in which the high-melting-point metal layer 60 and the low-melting-point metal layer 61 were laminated|stacked alternately. . In this case, the 1st, 2nd soluble conductors 13 and 14 are good also as the structure covered with the metal layer which comprises an outermost layer except the whole surface or a pair of mutually opposing side surfaces.

In addition, the 1st, 2nd soluble conductors 13 and 14 may laminate|stack the high-melting-point metal layer 60 in stripe shape partially on the surface of the low-melting-point metal layer 61 which comprises an inner layer. 13 : is a top view of the 1st, 2nd soluble conductors 13 and 14. FIG.

The 1st, 2nd soluble conductors 13 and 14 shown to Fig.13 (A) have the linear high-melting-point metal layer 60 on the surface of the low-melting-point metal layer 61 at predetermined intervals in the width direction. By forming a plurality in the longitudinal direction, a linear opening 62 is formed along the longitudinal direction, and the low-melting-point metal layer 61 is exposed from the opening 62 . As for the 1st, 2nd soluble conductors 13 and 14, when the low melting-point metal layer 61 is exposed from the opening part 62, the contact area of the molten low-melting-point metal and high-melting-point metal increases, and the high-melting-point metal layer 60 ) can further accelerate the erosion action to improve the fusing ability. The opening 62 can be formed by, for example, performing partial plating of the metal constituting the high-melting-point metal layer 60 to the low-melting-point metal layer 61 .

Moreover, the 1st, 2nd soluble conductors 13 and 14 are linear high melting points at predetermined intervals in the longitudinal direction on the surface of the low-melting-point metal layer 61, as shown in FIG.13(B). By forming two or more metal layers 60 in the width direction, you may form the linear opening part 62 along the width direction.

Moreover, while the 1st, 2nd soluble conductors 13 and 14 form the high-melting-point metal layer 60 on the surface of the low-melting-point metal layer 61, as shown in FIG. 14, the high-melting-point metal layer 60 ) A circular opening 63 is formed over the entire surface, and the low-melting-point metal layer 61 may be exposed from the opening 63 . The opening 63 can be formed by, for example, performing partial plating of the metal constituting the high-melting-point metal layer 60 to the low-melting-point metal layer 61 .

As for the 1st, 2nd soluble conductors 13 and 14, when the low melting-point metal layer 61 is exposed from the opening part 63, the contact area of the molten low-melting-point metal and high-melting-point metal increases, and erosion of a high-melting-point metal By further promoting the action, it is possible to improve the fusing property.

Moreover, the 1st, 2nd soluble conductors 13 and 14 form many opening parts 64 in the refractory-point metal layer 60 used as an inner layer, as shown in FIG. 15, This refractory-point metal layer 60 ), a low-melting-point metal layer 61 may be formed using a plating technique or the like to fill the opening 64 . Thereby, as for the 1st, 2nd soluble conductors 13 and 14, since the area in which the melting|fusing low-melting-point metal contact|connects high-melting-point metal increases, a low-melting-point metal can corrode a high-melting-point metal in a shorter time.

Moreover, it is preferable that the 1st, 2nd soluble conductors 13 and 14 form the volume of the low-melting-point metal layer 61 more than the volume of the high-melting-point metal layer 60. As shown in FIG. When the 1st, 2nd soluble conductors 13 and 14 are heated by the high-melting-point metal body 15, a low-melting-point metal melts, and a high-melting-point metal is corroded, and by this, it can melt|fuse and cut rapidly. . Therefore, the 1st, 2nd soluble conductors 13 and 14 promote this erosion action by forming the volume of the low-melting-point metal layer 61 more than the volume of the high-melting-point metal layer 60, and the 1st, A short circuit can be performed between the second electrodes 11 and 12 .

1, 40, 50: switch element
2: switch
10: insulated substrate
10a: surface
10f : back side
11: first electrode
12: second electrode
13: first soluble conductor
14: second soluble conductor
15: high melting point metal body
16: insulating layer
17: solder for connection
18 : flux
19: connection part
20: cover member
21: side wall
22: ceiling surface part
23: cover electrode
30: alarm circuit
31 : alarm
32: function circuit

Claims (33)

an insulated substrate;
first and second electrodes formed adjacent to each other on the insulating substrate;
a first soluble conductor mounted on the first electrode;
It is formed on the insulating substrate and has a high-melting-point metal body having a higher melting point than that of the first soluble conductor,
The said 1st soluble conductor contains a low melting-point metal and the high-melting-point metal of melting|fusing point higher than the said low-melting-point metal laminated|stacked on the said low melting-point metal,
Surface mounted by reflow mounting,
The melting point of the low-melting-point metal is less than or equal to the connection temperature by the reflow mounting,
The high-melting-point metal body conducts a current within the rating at normal time,
The first soluble conductor is melted by heat generated by an overcurrent flowing in the case of abnormality of the high-melting-point metal body, and the first electrode and the second electrode are connected through the molten conductor of the first soluble conductor, and electrically short-circuited. do it,
After the said high-melting-point metal body melts a said 1st soluble conductor and short-circuits a said 1st, 2nd electrode, the switch element melt|disconnected. an insulated substrate;
first and second electrodes formed adjacent to each other on the insulating substrate;
a first soluble conductor mounted on the first electrode;
It is formed on the insulating substrate and has a high-melting-point metal body having a higher melting point than that of the first soluble conductor,
An insulating layer is formed on a region except for the tip of the first electrode,
An opening is formed in a part of the insulating layer,
The said 1st soluble conductor is connected by the connection solder in the said opening part with the front-end|tip of the said 1st electrode,
The high-melting-point metal body conducts a current within the rating at normal time,
The switch element which melts the said 1st soluble conductor by heat_generation|fever by the overcurrent which flows at the time of the abnormality of the said high-melting-point metal body, connects the said 1st electrode and a 2nd electrode through this molten conductor, and electrically short-circuits. 3. The method of claim 2,
After the said high-melting-point metal body melts a said 1st soluble conductor and short-circuits a said 1st, 2nd electrode, the switch element melt|disconnected. 4. The method of claim 1 or 3,
The high-melting-point metal body is a switch element that is fused by its own Joule heat. 3. The method of claim 1 or 2,
The switch element in which the 2nd soluble conductor is mounted on the said 2nd electrode. 3. The method of claim 1 or 2,
The high-melting-point metal body is a switch element including an electrode pattern laminated on the surface of the insulating substrate. 7. The method of claim 6,
The said high-melting-point metal body is a metal which has silver or copper as a main component, The switch element. 7. The method of claim 6,
The electrode pattern of the high-melting-point metal body is relatively thin in a position close to the first soluble conductor, and the current is concentrated, thereby a switch element having a heat generating portion that generates heat locally at a high temperature. 3. The method of claim 1 or 2,
A switch element in which the high-melting-point metal body is covered with an insulating layer. 7. The method of claim 6,
A switch element in which an insulating layer is formed between the high-melting-point metal body and the insulating substrate. 10. The method of claim 9,
The insulating layer is a switch element containing glass as a main component. 3. The method of claim 1 or 2,
The high-melting-point metal body is a switch element that is a foil or wire containing copper or silver as a main component. 3. The method of claim 1 or 2,
The insulating substrate is a ceramic substrate. 3. The method of claim 1 or 2,
The said 1st electrode in which the said 1st soluble conductor was mounted, and the said high-melting-point metal body are connected. 3. The method of claim 1 or 2,
The switch element in which the said 1st, 2nd electrode and the said high melting-point metal body are arrange|positioned side by side on the same plane of the said insulating substrate. 3. The method of claim 1 or 2,
One side of the said insulating substrate WHEREIN: The switch element in which the said 1st, 2nd electrode is laminated|stacked on the said high-melting-point metal body via an insulating layer. 3. The method of claim 1 or 2,
The first and second electrodes are disposed on one side of the insulating substrate, the high melting point metal body is disposed on the other side of the insulating substrate, and at least the first soluble conductor mounted on the first electrode and the A switch element in which a high-melting-point metal body is overlapped. 3. The method of claim 2,
The said 1st soluble conductor is a soldering switch element. 3. The method of claim 1 or 2,
The said 1st soluble conductor contains a low-melting-point metal and a high-melting-point metal,
A switch element in which the low-melting-point metal is melted by the heat of the high-melting-point metal body to erode the high-melting-point metal. 20. The method of claim 19,
The low melting point metal is solder,
The high-melting-point metal is Ag, Cu, or an alloy containing Ag or Cu as a main component. 20. The method of claim 19,
As for the said 1st soluble conductor, the inner layer is the said high-melting-point metal, and the outer layer is the switch element whose covering structure of the said low-melting-point metal. 20. The method of claim 19,
As for the said 1st soluble conductor, the inner layer is the said low-melting-point metal, and the outer layer is the switch element whose coating structure of the said high-melting-point metal. 20. The method of claim 19,
The said 1st soluble conductor is a switch element whose said low-melting-point metal and the said high-melting-point metal are laminated|stacked structure laminated|stacked. 20. The method of claim 19,
The said 1st soluble conductor is a switch element whose multilayer structure of 4 or more layers in which the said low melting-point metal and the said high-melting-point metal were laminated|stacked alternately. 20. The method of claim 19,
As for the said 1st soluble conductor, the switch element in which the opening part is formed in the said high-melting-point metal formed in the surface of the said low-melting-point metal which comprises an inner layer. 20. The method of claim 19,
The first soluble conductor has a layer of the refractory metal having a plurality of openings, and a layer of the low-melting-point metal formed on the layer of the refractory metal, and the opening is filled with the low-melting-point metal. device. 20. The method of claim 19,
As for the said 1st soluble conductor, the volume of the said low-melting-point metal is a switch element with more volume than the volume of the said high-melting-point metal. 3. The method of claim 1 or 2,
A switch element in which a flux is coated on the first soluble conductor. 3. The method of claim 1 or 2,
The switch element in which any one of Ni/Au plating, Ni/Pd plating, and Ni/Pd/Au plating is coat|covered on the said 1st and 2nd electrode surface. 3. The method of claim 1 or 2,
It is formed on the insulating substrate and has a cover member for protecting the inside,
The cover member is a switch element in which a cover electrode is formed at a position overlapping the first and second electrodes. a switch part which is open to each other and connected to an external circuit, has first and second electrodes on at least one side of which a soluble conductor is mounted, and operates the external circuit when the first and second electrodes are short-circuited;
A fuse having a melting point higher than the melting point of the soluble conductor and connected to a functional circuit formed electrically independent of the switch unit is provided;
the first and second electrodes and the external circuit, and the fuse and the functional circuit are respectively connected by reflow mounting;
In the fuse, a current within the rated current flows during normal operation,
By the heat generated by the overcurrent flowing when the fuse by the functional circuit is abnormal, the soluble conductor is melted, and the first and second electrodes are short-circuited by the molten conductor of the soluble conductor to operate the external circuit switch circuit. 32. The method of claim 31,
The switch circuit in which electricity supply to the said fuse is stopped when a metal body is fused by its Joule heat. An operation circuit which is open to each other and has first and second electrodes on which a soluble conductor is mounted on at least one side, and operates an alarm by a switch unit in which the first and second electrodes are short-circuited;
a control circuit formed electrically independent of the operation circuit, the fuse having a melting point higher than the melting point of the fusible conductor;
The first and second electrodes, the alarm, the fuse, and the functional circuit are respectively connected by reflow mounting,
The fusible conductor is melted by the heat generated when the fuse is blown along with the overcurrent flowing in the case of an abnormality in the functional circuit, and the first and second electrodes are short-circuited by the molten conductor of the soluble conductor, and the alarm is activated. Alarm circuit that activates.

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